Driving circuit and driving method

Abstract

The invention discloses a driving circuit and a driving method, the driving circuit comprises a light emitting module, a power supply module, a control module and a voltage adjusting module, the light emitting module is electrically connected with the voltage adjusting module, the power supply module is electrically connected with the voltage adjusting module and the control module, and the control module is electrically connected with the voltage adjusting module; the light-emitting module is used for emitting light based on driving current; the control module is used for outputting a first control signal and transmitting the first control signal to the power supply module. The control module is further used for outputting a second control signal and transmitting the second control signal to the voltage adjusting module. The power supply module is used for outputting a first voltage to the voltage adjusting module under the control of the first control signal; and the voltage adjusting module is used for adjusting the first voltage into the second voltage under the control of the second control signal so as to control the size of the driving current. By arranging the voltage adjusting module, the problem of color cast of a display picture caused by different second voltages between different pixel areas can be solved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a driving circuit and a driving method. Background Art

[0002] Organic light-emitting displays are one of the hot topics in the field of flat panel display research today. Compared with liquid crystal displays, organic light-emitting displays have the advantages of low energy consumption, low production cost, self-luminescence, wide viewing angle and fast response speed. At present, in the field of flat panel displays such as mobile phones, PDAs, digital cameras, organic light-emitting displays have begun to replace traditional liquid crystal display panels.

[0003] At present, the brightness of organic light-emitting displays is generally controlled by pulse width modulation driving method, that is, a frame time is divided into several sub-frames, each sub-frame corresponds to a pulse cycle. In each pulse cycle, a low level indicates that the sub-pixel emits light, and a high level indicates that the sub-pixel does not emit light. Therefore, within a frame time, the higher the duty cycle of the low level, the longer the sub-pixel emits light, and the higher the brightness of the corresponding display.

[0004] In existing organic light-emitting displays, since the actual output current of the driver chip is different from the theoretical current value, the light-emitting diodes in a single pixel have a certain half-wave width and light decay phenomenon, which will cause deviation problems in the full-color display of the light-emitting diodes. At the same time, since the power supply voltage is different from the input point, the driving voltages corresponding to different pixels will be different, resulting in different currents. It is usually manifested as the farther away from the power supply end, the greater the resistance, the more obvious the current drop, and the greater the drop in the brightness of the light-emitting diode, resulting in uneven brightness. Summary of the invention

[0005] The present application provides a driving circuit and a driving method, which can solve the problem of color deviation of a display screen caused by different second voltages between different pixel areas by setting a voltage adjustment module to make the second voltages of different pixel areas consistent.

[0006] In a first aspect, an embodiment of the present application provides a driving circuit, characterized in that it includes: a light-emitting module, a power supply module, a control module and a voltage adjustment module, the light-emitting module is electrically connected to the voltage adjustment module, the power supply module is electrically connected to the voltage adjustment module and the control module, and the control module is electrically connected to the voltage adjustment module; the light-emitting module is used to emit light based on a driving current; the control module is used to output a first control signal and transmit it to the power supply module, and the control module is also used to output a second control signal and transmit it to the voltage adjustment module; the power supply module is used to output a first voltage to the voltage adjustment module under the control of the first control signal; the voltage adjustment module is used to adjust the first voltage to a second voltage under the control of the second control signal to control the magnitude of the driving current.

[0007] Optionally, in some embodiments of the present application, the power supply module includes a first transistor, a first electrode of the first transistor is electrically connected to a first power supply terminal, a second electrode of the first transistor is electrically connected to a first node, and a gate of the first transistor is electrically connected to the control module.

[0008] Optionally, in some embodiments of the present application, the light-emitting module includes a first resistor and a light-emitting device, one end of the first resistor is electrically connected to the voltage adjustment module, and the other end of the first resistor is electrically connected to the anode of the light-emitting device; the cathode of the light-emitting device is electrically connected to the second power supply terminal.

[0009] Optionally, in some embodiments of the present application, the voltage adjustment module includes a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor and a second resistor, a third resistor, a fourth resistor, and a fifth resistor, wherein the first electrode of the second transistor is electrically connected to the first node, the second electrode of the second transistor is electrically connected to the second node, and the gate of the second transistor is electrically connected to the control module; the first electrode of the third transistor is electrically connected to the second node, the second electrode of the third transistor is electrically connected to the third node, and the gate of the third transistor is electrically connected to the control module; the first electrode of the fourth transistor is electrically connected to the fourth node, the second electrode of the fourth transistor is electrically connected to the fifth node, and the gate of the fourth transistor is electrically connected to the control module; the first electrode of the fifth transistor is electrically connected to the sixth node, and the second electrode of the fifth transistor is electrically connected to the At the seventh node, the gate of the fifth transistor is electrically connected to the control module; the first electrode of the sixth transistor is electrically connected to the eighth node, the second electrode of the sixth transistor is electrically connected to the ninth node, and the gate of the sixth transistor is electrically connected to the control module; the third node is electrically connected to the fifth node, the seventh node and the ninth node, and one end of the first resistor is electrically connected to the ninth node; one end of the second resistor is electrically connected to the second node, and the other end of the second resistor is electrically connected to the fourth node; one end of the third resistor is electrically connected to the fourth node, and the other end of the second resistor is electrically connected to the sixth node; one end of the fourth resistor is electrically connected to the sixth node, and the other end of the second resistor is electrically connected to the eighth node; one end of the fifth resistor is electrically connected to the eighth node, and the other end of the second resistor is electrically connected to the second power supply end.

[0010] Optionally, in some embodiments of the present application, the voltage adjustment module also includes a seventh transistor, a first electrode of the seventh transistor is electrically connected to the first node, a second electrode of the seventh transistor is electrically connected to the eighth node, and a gate of the seventh transistor is electrically connected to the control module.

[0011] Optionally, in some embodiments of the present application, the first transistor, the second transistor, the third transistor, the fourth transistor, the fifth transistor, the sixth transistor and the seventh transistor are all transistors of the same type.

[0012] Optionally, in some embodiments of the present application, the second control signal includes a pulse width modulation signal, and the control module controls the voltage adjustment module to generate the second voltage through the pulse width modulation signal.

[0013] Optionally, in some embodiments of the present application, the control module controls the magnitude of the second voltage by adjusting the duty cycle of the pulse width control signal to adjust the magnitude of the driving current.

[0014] Optionally, in some embodiments of the present application, the magnitude of the driving current is:

[0015] Iout represents the magnitude of the driving current, VDD′ represents the second voltage, R1 represents the resistance value of the first resistor, and Duty represents the duty cycle of the control signal.

[0016] On the other hand, the present application provides a driving method, which is applied to the above-mentioned driving circuit, including: a control module outputs a first control signal and transmits it to a power supply module; under the control of the first control signal, the power supply module outputs a first voltage to a voltage adjustment module; the control module outputs a second control signal and transmits it to the voltage adjustment module; under the control of the second control signal, the voltage adjustment module adjusts the first voltage to a second voltage to control the size of the driving current; and the light-emitting module emits light based on the driving current.

[0017] The present application provides a driving circuit and a driving method, the driving circuit includes a light-emitting module, a power module, a control module and a voltage adjustment module, the light-emitting module is connected in series to the light-emitting circuit; the power module is electrically connected to the first power supply terminal, and the power module is used to transmit the first voltage to the first node; the control module is electrically connected to the power module, and the control module is used to provide a control signal, and the control signal controls the conduction and cutoff of the power module; the voltage adjustment module is electrically connected to the light-emitting module, the power module and the control module respectively, and the voltage adjustment module is used to adjust the magnitude of the second voltage under the control of the control signal. The driving circuit provided by the present application adjusts the second voltage of different pixel areas by setting a voltage adjustment module, ensures that the second voltage between pixels in the same row is consistent, ensures uniform brightness of the display screen, can solve the color deviation problem of the display screen caused by the different second voltages between different pixel areas, and improves the display effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. The drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of the structure of a driving circuit provided in an embodiment of the present application;

[0020] Figure 2 This is a first circuit diagram of a driving circuit provided in an embodiment of the present application;

[0021] Figure 3 is a schematic diagram of the sub-frame light-emitting time in the driving circuit provided in an embodiment of the present application;

[0022] Figure 4 is a second circuit schematic diagram of a driving circuit provided in an embodiment of the present application;

[0023] Figure 5 It is a flowchart of the driving method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0025] The embodiments of the present application provide a driving circuit and a driving method. By setting a voltage adjustment module, the second voltages of different pixel areas are made consistent, which can solve the color deviation problem of the display screen caused by the different second voltages between different pixel areas. The following are described in detail. It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments. In addition, in the description of the present application, the term "including" means "including but not limited to". The terms "first", "second", "third", etc. are used only as labels to distinguish different objects, rather than to describe a specific order.

[0026] The transistors used in all embodiments of the present application may be thin film transistors or field effect transistors or other devices with the same characteristics. Since the source and drain of the transistors used here are symmetrical, their source and drain are interchangeable. In the embodiments of the present application, in order to distinguish the two poles of the transistor other than the gate, one of the source and the drain is called the first electrode, and the other of the source and the drain is called the second electrode. According to the form in the accompanying drawings, the middle end of the switching transistor is defined as the gate, the signal input end is the source, and the output end is the drain. In addition, the transistors used in the embodiments of the present application are N-type transistors or P-type transistors, wherein the N-type transistor is turned on when the gate is at a high potential and is turned off when the gate is at a low potential; the P-type transistor is turned on when the gate is at a low potential and is turned off when the gate is at a high potential. In the embodiments of the present application, the light-emitting device D may be Mini-LED or Micro-LED.

[0027] See also Figure 1 and Figure 2 , Figure 1 A schematic diagram of the structure of a driving circuit provided in an embodiment of the present application; Figure 2 is a first circuit diagram of a driving circuit provided in an embodiment of the present application. Figure 1 As shown, the embodiment of the present application provides a driving circuit 100, including: a light-emitting module 10, a power module 20, a control module 30 and a voltage adjustment module 40, the light-emitting module 10 is electrically connected to the voltage adjustment module 40, the power module 20 is electrically connected to the voltage adjustment module 40 and the control module 30, and the control module 30 is electrically connected to the voltage adjustment module 40; the light-emitting module 10 is used to emit light based on a driving current; the control module 30 is used to output a first control signal and transmit it to the power module 20, and the control module 30 is also used to output a second control signal and transmit it to the voltage adjustment module 40; the power module 20 is used to output a first voltage VDD to the voltage adjustment module 40 under the control of the first control signal; the voltage adjustment module 40 is used to adjust the first voltage VDD to a second voltage VDD' under the control of the second control signal to control the driving current I out size.

[0028] The driving circuit provided in the present application is provided with a voltage adjustment module 40 to adjust the second voltage VDD' of different pixel areas, thereby ensuring that the second voltage VDD' between pixels in the same row is consistent and the brightness of the displayed image is uniform. This can solve the color deviation problem of the displayed image caused by the different second voltage VDD' between different pixel areas and improve the display effect.

[0029] In the embodiment of the present application, the power module 20 includes a first transistor T1, a first electrode of the first transistor T1 is electrically connected to the first power supply terminal, a second electrode of the first transistor T1 is electrically connected to the first node A, and a gate of the first transistor T1 is electrically connected to the control module 30.

[0030] In the embodiments of the present application, Figure 2 As shown, the light emitting module 10 includes a first resistor R1 and a light emitting device LED, one end of the first resistor R1 is electrically connected to the voltage adjustment module 40, and the other end of the first resistor R1 is electrically connected to the anode of the light emitting device LED; the cathode of the light emitting device LED is electrically connected to the second power supply terminal VSS.

[0031] It should be noted that the first power supply terminal VDD and the second power supply terminal VSS are both used to output a preset voltage value. In addition, in the embodiment of the present application, the potential of the first power supply terminal VDD is greater than the potential of the second power supply terminal VSS. Specifically, the potential of the second power supply terminal VSS can be the potential of the ground terminal. Of course, it can be understood that the potential of the second power supply terminal VSS can also be other.

[0032] In the embodiment of the present application, the voltage adjustment module 40 includes a first transistor T2, a third transistor T3, a fourth transistor T4, a fifth transistor T5, a sixth transistor T6 and a second resistor R2, a third resistor R3, a fourth resistor R4, and a fifth resistor R5, wherein the first electrode of the first transistor T2 is electrically connected to the first node A, the second electrode of the first transistor T2 is electrically connected to the second node B, and the gate of the first transistor T2 is electrically connected to the control module 30; the first electrode of the third transistor T3 is electrically connected to the second node B, the second electrode of the third transistor T3 is electrically connected to the third node C, and the gate of the third transistor T3 is electrically connected to the control module 30; the first electrode of the fourth transistor T4 is electrically connected to the fourth node D, the second electrode of the fourth transistor T4 is electrically connected to the fifth node E, and the gate of the fourth transistor T4 is electrically connected to the control module 30; the first electrode of the fifth transistor T5 is electrically connected to the sixth node F, and the fifth transistor T5 is electrically connected to the sixth node F. The second electrode of the body transistor T5 is electrically connected to the seventh node G, and the gate of the fifth transistor T5 is electrically connected to the control module 30; the first electrode of the sixth transistor T6 is electrically connected to the eighth node H, the second electrode of the sixth transistor T6 is electrically connected to the ninth node I, and the gate of the sixth transistor T6 is electrically connected to the control module 30; the third node C is electrically connected to the fifth node E, the seventh node G and the ninth node I, and one end of the first resistor R1 is electrically connected to the ninth node I; one end of the second resistor R2 is electrically connected to the second node B, and the other end of the second resistor R2 is electrically connected to the fourth node D; one end of the third resistor R3 is electrically connected to the fourth node D, and the other end of the second resistor R2 is electrically connected to the sixth node F; one end of the fourth resistor R4 is electrically connected to the sixth node F, and the other end of the second resistor R2 is electrically connected to the eighth node H; one end of the fifth resistor R5 is electrically connected to the eighth node H, and the other end of the second resistor R2 is electrically connected to the second power supply terminal VSS.

[0033] In the embodiment of the present application, the first transistor T1, the first transistor T2, the third transistor T3, the fourth transistor T4, the fifth transistor T5, and the sixth transistor T6 are all transistors of the same type. Specifically, they can be one or more of a low-temperature polysilicon thin film transistor, an oxide semiconductor thin film transistor or an amorphous silicon thin film transistor, and a field effect transistor. Among them, the resistance values ​​of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, and the fifth resistor R5 can be the same or different. Those skilled in the art can set and debug according to actual needs to select a suitable resistance value, which is not limited in the present application.

[0034] In the embodiment of the present application, the second control signal includes a pulse width modulation signal, and the control module 30 controls the voltage adjustment module 40 to generate the second voltage VDD' through the pulse width modulation signal. The control module 30 controls the magnitude of the second voltage VDD' and adjusts the driving current I outThe size of the light emitting module 10 is adjusted to thereby adjust the light emitting brightness.

[0035] Specifically, after the control module 30 receives the frame image to be displayed, it generates N sub-frame images from the received frame image to be displayed according to the number N of sub-frames in a frame in the preset pulse width modulation parameters, and configures the luminous time and the corresponding luminous brightness for each sub-frame image in the N sub-frame images; then the display panel is controlled to display each sub-frame image in sequence, and when displaying each sub-frame image, the pixels that need to emit light in the sub-frame image are controlled to emit light according to the corresponding luminous brightness during the luminous time period corresponding to the sub-frame image. However, in each sub-frame image, the luminous brightness corresponding to each pixel is determined based on the display brightness corresponding to each pixel in the frame image to be displayed and the luminous time configured for the sub-frame image, and the luminous brightness corresponding to each pixel is selected from a range greater than or equal to the minimum luminous brightness of the pixel and less than or equal to the maximum luminous brightness of the pixel. Preferably, as Figure 3 As shown, the number of subframes N in one frame is equal to 4, and the luminous time of each subframe image configuration is equal, that is, t1 = t2 = t3 = t4, Figure 3 Only two different luminous times PWM1 and PWM2 are shown, wherein the luminous time of the subframe image can also be adjusted as needed. Further, the number N of subframes in a frame can also be 5 or 6, and the luminous time configured for each subframe image can be equal or unequal.

[0036] That is, within one frame time, the display brightness of the pixel is not only determined by the light-emitting time of the light-emitting subframe, wherein the light-emitting time of the pixel is determined by the duty cycle of the pulse width modulation signal provided by the control module 30; at the same time, the display brightness of the pixel is also determined by the light-emitting brightness of the pixel, wherein the light-emitting brightness of the pixel is determined by the size of the second voltage VDD'. By setting the voltage adjustment module 40 to adjust the size of the second voltage VDD' according to the pulse width modulation signal, not only can the low grayscale brightness be accurately displayed, but also a smaller number of subframes can be used, and at the same time, the uniformity of the display brightness of the pixels within the surface is guaranteed to avoid color deviation.

[0037] In the embodiment of the present application, the driving current is:

[0038]

[0039] Among them, I out represents the driving current, VDD' represents the second voltage VDD', R1 represents the resistance of the first resistor R1, and Duty represents the duty cycle of the control signal.

[0040] Specifically, the control module 30 provides a pulse width modulation signal to the power module 20 to control the first transistor T1 to be turned on, so that the power module 20 can transmit the first voltage VDD to the voltage adjustment module 40, and the light-emitting time of the pixel is determined by the duty cycle of the pulse width modulation signal provided by the control module 30; the voltage adjustment module 40 generates a different second voltage VDD' under the control of the pulse width modulation signal.

[0041] In the embodiment of the present application, the voltage adjustment module 40 generates the second voltage VDD' of different magnitudes in the following multiple adjustment methods:

[0042] The first adjustment method: the first transistor T2 and the third transistor T3 are turned on, and the fourth transistor T4, the fifth transistor T5 and the sixth transistor T6 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is consistent with the first voltage VDD, that is, VDD'=VDD, where VDD represents the first voltage VDD.

[0043] Second adjustment method: the first transistor T2 and the sixth transistor T6 are turned on, and the third transistor T3, the fourth transistor T4 and the fifth transistor T5 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is:

[0044]

[0045] Wherein, VDD represents the first voltage VDD.

[0046] The third adjustment method: the first transistor T2 and the fifth transistor T5 are turned on, and the third transistor T3, the fourth transistor T4 and the sixth transistor T6 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is:

[0047]

[0048] Wherein, VDD represents the first voltage VDD.

[0049] Fourth adjustment method: the first transistor T2 and the fourth transistor T4 are turned on, and the third transistor T3, the fifth transistor T5 and the sixth transistor T6 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is:

[0050]

[0051] Wherein, VDD represents the first voltage VDD.

[0052] In the embodiment of the present application, the larger the pixel resistance that is farther away from the power module 20, the more obvious the current drop is. Therefore, the pixels corresponding to the farther area select a higher adjustment method of the second voltage VDD' to increase their driving current; on the contrary, the smaller the pixel resistance that is closer to the power module 20, the less obvious the current drop is. Therefore, the pixels corresponding to the closer area select a relatively low adjustment method of the second voltage VDD' to make the second voltage VDD' consistent with or relatively high to the first voltage VDD, so that the driving current remains unchanged or relatively increases. Such a design ensures that the current of the light-emitting device LED corresponding to the pixel in the farther area and the current of the light-emitting device LED corresponding to the pixel in the closer area are consistent, that is, the driving current is consistent, thereby avoiding display abnormalities caused by uneven brightness of pixels in different areas.

[0053] As a specific method of this application, please refer to Figure 4 , Figure 4 Schematic diagram of the sub-frame luminous time in the driving circuit provided in the embodiment of the present application. Figure 4 As shown, the present application also provides a driving circuit 200, the difference between the driving circuit 200 and the driving circuit 100 is that the voltage adjustment module 40 in the driving circuit 200 further includes a seventh transistor T7, the first electrode of the seventh transistor T7 is electrically connected to the first node A, the second electrode of the seventh transistor T7 is electrically connected to the eighth node H, and the gate of the seventh transistor T7 is electrically connected to the control module 30. Among them, the second electrode of the seventh transistor T7 is electrically connected to the eighth node H to play a role in boosting the voltage.

[0054] In the embodiment of the present application, the power module 20 includes a first transistor T1, a first electrode of the first transistor T1 is electrically connected to the first power supply terminal, a second electrode of the first transistor T1 is electrically connected to the first node A, and a gate of the first transistor T1 is electrically connected to the control module 30.

[0055] In the embodiment of the present application, the light emitting module 10 includes a first resistor R1 and a light emitting device LED, one end of the first resistor R1 is electrically connected to the voltage adjustment module 40, and the other end of the first resistor R1 is electrically connected to the anode of the light emitting device LED; the cathode of the light emitting device LED is electrically connected to the second power supply terminal VSS. The first resistor R1 plays the role of current limiting and voltage dividing.

[0056] In the embodiment of the present application, the voltage adjustment module 40 includes a first transistor T2, a third transistor T3, a fourth transistor T4, a fifth transistor T5, a sixth transistor T6 and a second resistor R2, a third resistor R3, a fourth resistor R4, and a fifth resistor R5, wherein the first electrode of the first transistor T2 is electrically connected to the first node A, the second electrode of the first transistor T2 is electrically connected to the second node B, and the gate of the first transistor T2 is electrically connected to the control module 30; the first electrode of the third transistor T3 is electrically connected to the second node B, the second electrode of the third transistor T3 is electrically connected to the third node C, and the gate of the third transistor T3 is electrically connected to the control module 30; the first electrode of the fourth transistor T4 is electrically connected to the fourth node D, the second electrode of the fourth transistor T4 is electrically connected to the fifth node E, and the gate of the fourth transistor T4 is electrically connected to the control module 30; the first electrode of the fifth transistor T5 is electrically connected to the sixth node F, and the fifth transistor T5 is electrically connected to the sixth node F. The second electrode of the body transistor T5 is electrically connected to the seventh node G, and the gate of the fifth transistor T5 is electrically connected to the control module 30; the first electrode of the sixth transistor T6 is electrically connected to the eighth node H, the second electrode of the sixth transistor T6 is electrically connected to the ninth node I, and the gate of the sixth transistor T6 is electrically connected to the control module 30; the third node C is electrically connected to the fifth node E, the seventh node G and the ninth node I, and one end of the first resistor R1 is electrically connected to the ninth node I; one end of the second resistor R2 is electrically connected to the second node B, and the other end of the second resistor R2 is electrically connected to the fourth node D; one end of the third resistor R3 is electrically connected to the fourth node D, and the other end of the second resistor R2 is electrically connected to the sixth node F; one end of the fourth resistor R4 is electrically connected to the sixth node F, and the other end of the second resistor R2 is electrically connected to the eighth node H; one end of the fifth resistor R5 is electrically connected to the eighth node H, and the other end of the second resistor R2 is electrically connected to the second power supply terminal VSS.

[0057] In the embodiment of the present application, the first transistor T1, the first transistor T2, the third transistor T3, the fourth transistor T4, the fifth transistor T5, the sixth transistor T6 and the seventh transistor T7 are all transistors of the same type. Specifically, they can be one or more of low-temperature polysilicon thin film transistors, oxide semiconductor thin film transistors or amorphous silicon thin film transistors, and field effect transistors. Among them, the resistance values ​​of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4 and the fifth resistor R5 can be the same or different. Those skilled in the art can set and debug according to actual needs to select a suitable resistance value, which is not limited in the present application.

[0058] In the embodiment of the present application, the second control signal includes a pulse width modulation signal, and the control module 30 controls the voltage adjustment module 40 to generate the second voltage VDD' through the pulse width modulation signal. The control module 30 controls the magnitude of the second voltage VDD' by adjusting the duty cycle of the pulse width control signal to adjust the light emitting brightness of the light emitting module 10.

[0059] In the embodiment of the present application, within one frame time, the display brightness of the pixel is not only determined by the light-emitting time of the light-emitting sub-frame, wherein the light-emitting time of the pixel is determined by the duty cycle of the pulse width modulation signal provided by the control module 30; at the same time, the display brightness of the pixel is also determined by the light-emitting brightness of the pixel, wherein the light-emitting brightness of the pixel is determined by the size of the second voltage VDD'. By setting the voltage adjustment module 40 to adjust the size of the second voltage VDD' according to the pulse width modulation signal, not only can the low grayscale brightness be accurately displayed, but also a smaller number of sub-frames can be used, and at the same time, the uniformity of the display brightness of the pixels within the surface is guaranteed to avoid color deviation.

[0060] In the embodiment of the present application, the driving current is:

[0061]

[0062] Among them, I out represents the driving current, VDD' represents the second voltage VDD', R1 represents the resistance of the first resistor R1, and Duty represents the duty cycle of the control signal.

[0063] Specifically, the control module 30 provides a pulse width modulation signal to the power module 20 to control the first transistor T1 to be turned on, so that the power module 20 can transmit the first voltage VDD to the voltage adjustment module 40, and the light-emitting time of the pixel is determined by the duty cycle of the pulse width modulation signal provided by the control module 30; the voltage adjustment module 40 generates a different second voltage VDD' under the control of the pulse width modulation signal.

[0064] In the embodiment of the present application, the voltage adjustment module 40 generates the second voltage VDD' of different magnitudes in the following multiple adjustment methods:

[0065] The first adjustment method: the first transistor T2 and the third transistor T3 are turned on, and the fourth transistor T4, the fifth transistor T5, the sixth transistor T6 and the seventh transistor T7 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is consistent with the first voltage VDD, that is, VDD'=VDD, where VDD represents the first voltage VDD.

[0066] Second adjustment method: the first transistor T2 and the sixth transistor T6 are turned on, and the third transistor T3, the fourth transistor T4, the fifth transistor T5 and the seventh transistor T7 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is:

[0067]

[0068] The third adjustment method: the first transistor T2 and the fifth transistor T5 are turned on, and the third transistor T3, the fourth transistor T4, the sixth transistor T6 and the seventh transistor T7 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is:

[0069]

[0070] Fourth adjustment method: the first transistor T2 and the fourth transistor T4 are turned on, and the third transistor T3, the fifth transistor T5, the sixth transistor T6 and the seventh transistor T7 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is:

[0071]

[0072] Fifth adjustment method: the seventh transistor T7 and the sixth transistor T6 are turned on, and the first transistor T2, the third transistor T3, the fourth transistor T4 and the fifth transistor T5 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is consistent with the first voltage VDD, that is, VDD'=VDD.

[0073] The sixth adjustment method: the seventh transistor T7 and the fifth transistor T5 are turned on, and the first transistor T2, the third transistor T3, the fourth transistor T4 and the sixth transistor T6 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is:

[0074]

[0075] The seventh adjustment method: the seventh transistor T7 and the fourth transistor T4 are turned on, and the first transistor T2, the third transistor T3, the fifth transistor T5 and the sixth transistor T6 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is:

[0076]

[0077] The eighth adjustment method: the seventh transistor T7 and the third transistor T3 are turned on, and the first transistor T2, the fourth transistor T4, the fifth transistor T5 and the sixth transistor T6 are turned off. At this time, the second voltage VDD' output by the voltage adjustment module 40 is:

[0078]

[0079] In the embodiment of the present application, the larger the pixel resistance that is farther away from the power module 20, the more obvious the current drop is. Therefore, the pixels corresponding to the farther area select a higher adjustment method of the second voltage VDD' to increase their driving current; on the contrary, the smaller the pixel resistance that is closer to the power module 20, the less obvious the current drop is. Therefore, the pixels corresponding to the closer area select a relatively low adjustment method of the second voltage VDD' to make the second voltage VDD' consistent with or relatively high to the first voltage VDD, so that the driving current remains unchanged or relatively increases. Such a design ensures that the current of the light-emitting device LED corresponding to the pixel in the farther area and the current of the light-emitting device LED corresponding to the pixel in the closer area are consistent, that is, the driving current is consistent, thereby avoiding display abnormalities caused by uneven brightness of pixels in different areas.

[0080] The driving circuit provided in the present application is provided with a voltage adjustment module 40 to adjust the second voltage VDD' of different pixel areas, thereby ensuring that the second voltage VDD' between pixels in the same row is consistent and the brightness of the displayed image is uniform. This can solve the color deviation problem of the displayed image caused by the different second voltage VDD' between different pixel areas and improve the display effect.

[0081] See also Figure 5 , Figure 5 : is a flow chart of a driving method provided by an embodiment of the present application. As shown in the figure, the present application provides a driving method, including:

[0082] S10, the control module 30 outputs a first control signal and transmits it to the power module 20; under the control of the first control signal, the power module 20 outputs a first voltage VDD to the voltage adjustment module 40;

[0083] S20, the control module 30 outputs a second control signal and transmits it to the voltage adjustment module 40; under the control of the second control signal, the voltage adjustment module 40 adjusts the first voltage VDD to a second voltage VDD' to control the driving current I out size;

[0084] S30, the light emitting module 10 is driven by the driving current I out Glow.

[0085] In the embodiment of the present application, within one frame time, the display brightness of the pixel is not only determined by the light-emitting time of the light-emitting sub-frame, wherein the light-emitting time of the pixel is determined by the duty cycle of the pulse width modulation signal provided by the control module 30; at the same time, the display brightness of the pixel is also determined by the light-emitting brightness of the pixel, wherein the light-emitting brightness of the pixel is determined by the size of the second voltage VDD'. By setting the voltage adjustment module 40 to adjust the size of the second voltage VDD' according to the pulse width modulation signal, not only can the low grayscale brightness be accurately displayed, but also a smaller number of sub-frames can be used, and at the same time, the uniformity of the display brightness of the pixels within the surface is guaranteed to avoid color deviation.

[0086] The driving circuit provided in the present application is provided with a voltage adjustment module 40 to adjust the second voltage VDD' of different pixel areas, thereby ensuring that the second voltage VDD' between pixels in the same row is consistent and the brightness of the displayed image is uniform. This can solve the color deviation problem of the displayed image caused by the different second voltage VDD' between different pixel areas and improve the display effect.

[0087] The above is a detailed introduction to a driving circuit and a driving method provided in an embodiment of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A driving circuit, characterized in that: It includes: a light emitting module, a power module, a control module and a voltage regulating module, wherein the light emitting module is electrically connected to the voltage regulating module, the power module is electrically connected to the voltage regulating module and the control module, and the control module is electrically connected to the voltage regulating module; The light emitting module is used to emit light based on a driving current; The control module is used to output a first control signal and transmit it to the power module, and the control module is also used to output a second control signal and transmit it to the voltage adjustment module; The power supply module is used for outputting a first voltage to the voltage adjustment module under the control of the first control signal; The voltage adjustment module is used to adjust the first voltage to a second voltage under the control of the second control signal, so as to control the magnitude of the driving current; in The power module comprises a first transistor, a first electrode of the first transistor is electrically connected to a first power terminal, a second electrode of the first transistor is electrically connected to a first node, and a gate of the first transistor is electrically connected to the control module; The voltage adjustment module includes a sixth transistor and a seventh transistor, the first electrode of the sixth transistor is electrically connected to the eighth node, the second electrode of the sixth transistor is electrically connected to the ninth node, the gate of the sixth transistor is electrically connected to the control module, the first electrode of the seventh transistor is electrically connected to the first node, the second electrode of the seventh transistor is electrically connected to the eighth node, and the gate of the seventh transistor is electrically connected to the control module.

2. The driving circuit according to claim 1, characterized in that: The light emitting module further comprises a first resistor and a light emitting device, one end of the first resistor is electrically connected to the voltage adjustment module, the other end of the first resistor is electrically connected to the anode of the light emitting device; the cathode of the light emitting device is electrically connected to the second power supply terminal.

3. The driving circuit according to claim 1, characterized in that: The voltage adjustment module further includes a second transistor, a third transistor, a fourth transistor, a fifth transistor and a second resistor, a third resistor, a fourth resistor, and a fifth resistor, wherein: A first electrode of the second transistor is electrically connected to the first node, a second electrode of the second transistor is electrically connected to a second node, and a gate of the second transistor is electrically connected to the control module; The first electrode of the third transistor is electrically connected to the second node, the second electrode of the third transistor is electrically connected to the third node, and the gate of the third transistor is electrically connected to the control module; The first electrode of the fourth transistor is electrically connected to the fourth node, the second electrode of the fourth transistor is electrically connected to the fifth node, and the gate of the fourth transistor is electrically connected to the control module; The first electrode of the fifth transistor is electrically connected to the sixth node, the second electrode of the fifth transistor is electrically connected to the seventh node, and the gate of the fifth transistor is electrically connected to the control module; The second electrode of the sixth transistor is electrically connected to the ninth node, and the gate of the sixth transistor is electrically connected to the control module; The third node is electrically connected to the fifth node, the seventh node and the ninth node, and one end of the first resistor is electrically connected to the ninth node; One end of the second resistor is electrically connected to the second node, and the other end of the second resistor is electrically connected to the fourth node; One end of the third resistor is electrically connected to the fourth node, and the other end of the second resistor is electrically connected to the sixth node; One end of the fourth resistor is electrically connected to the sixth node, and the other end of the second resistor is electrically connected to the eighth node; One end of the fifth resistor is electrically connected to the eighth node, and the other end of the second resistor is electrically connected to the second power supply end.

4. The driving circuit according to claim 3, characterized in that: When the first voltage is equal to the first voltage, the first transistor and the third transistor are turned on, and the fourth transistor, the fifth transistor, and the sixth transistor are turned off.

5. The driving circuit according to claim 3, characterized in that: When the second voltage is less than the first voltage, the first transistor and the sixth transistor are turned on, and the third transistor, the fourth transistor, and the fifth transistor are turned off.

6. The driving circuit according to claim 3, characterized in that: When the second voltage is less than the first voltage, the first transistor and the sixth transistor are turned on, and the third transistor, the fourth transistor, and the fifth transistor are turned off.

7. The driving circuit according to claim 3, characterized in that: When the second voltage is less than the first voltage, the first transistor and the fifth transistor are turned on, and the third transistor, the fourth transistor and the sixth transistor are turned off.

8. The driving circuit according to claim 3, characterized in that: When the second voltage is less than the first voltage, the first transistor and the fourth transistor are turned on, and the third transistor, the fifth transistor, and the sixth transistor are turned off.

9. The driving circuit according to claim 1, characterized in that: The second control signal includes a pulse width modulation signal, the pulse width modulation signal controls the voltage adjustment module to generate the second voltage, the control module controls the magnitude of the second voltage by adjusting the duty cycle of the pulse width control signal, and the magnitude of the driving current is: I out represents the magnitude of the driving current, VDD' represents the second voltage, R1 represents the resistance value of the first resistor, and Duty represents the duty cycle of the control signal.

10. A driving method, applied to the driving circuit according to any one of claims 1 to 9, characterized in that: include: The control module outputs a first control signal and transmits it to the power module; The power module outputs a first voltage to the voltage adjustment module under the control of the first control signal; The control module outputs a second control signal and transmits it to the voltage adjustment module; under the control of the second control signal, the voltage adjustment module adjusts the first voltage to a second voltage to control the magnitude of the driving current; The light emitting module emits light based on the driving current.

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